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Pass by noise is a complex test that requires meeting several different standards with regard to the physical track layout, measurement systems, data acquisition, triggering, processing and analysis. Overview of the pertinent standards for Tire and Vehicle pass by testing is provided along with the description of development of an advanced solution to meet our specific needs. Key features of the solution are provided along with the lessons learned from our operation of the system at our facility and several other test tracks.

When testing dynamic structures, it is important to note that the dynamic system in question may be submerged into a fluid during operation and to properly test the structure under the same condition in order to understand the true dynamic parameters of the system. In this way, the mass and stiffness coupling to the particular fluid, for the case of this study, automatic transmission fluid, may be taken into account. This is especially important in light structures where the coupling between the fluid mass and the structural mass may be great. A structure was tested with a laser vibrometer using several impact methods in open air to determine which impact method would be most suitable for submerged testing. The structure was then submerged in transmission fluid with an accelerometer attached and subsequently tested and compared to the previous results.

In response to a growing need for a practical and technically valid method for measuring exhaust sound pressure levels (SPL) of on-highway motorcycles, the SAE Motorcycle Technical Steering Committee has developed Surface Vehicle Recommended Practice J28251, “Measurement of Exhaust Sound Pressure Levels of Stationary On-Highway Motorcycles,” which includes a new stationary sound test procedure and recommendations for limit values. Key goals of the development process included: minimal equipment requirements, ease of implementation by non-technical personnel, and consistency with the federal EPA requirements; in particular, vehicles compliant with the EPA requirements should not fail when assessed using J2825. Development of the recommended practice involved a comprehensive field study of 25 motorcycles and 76 different exhaust systems, ranging from relatively quiet OEM systems to unbaffled, aftermarket exhaust systems.

The development and validation of a brake pad insulator damping measurement procedure by the SAE Brake NVH Standards Committee was presented at the 2010 SAE Brake Colloquium (Paper 2010-01-1685). In Europe, in 2010, the EKB Working Group identified the need to develop a similar procedure, and started some activities which lead to the release of a standard similar but different than the SAE J3001. The SAE and EKB working groups agreed that having a global standard was of paramount importance, so the 2 groups decided to meet in November of 2010 to flush out the details of the J3001 global procedure. The details of the new test procedure, test setup and recommendation for proper test practices are described in this paper. This description provides an excellent foundation for evaluating the insulator damping properties over a range of temperatures and frequencies.

Advanced powertrain test, which is simulating real road load condition, was performed on the dynamic test bed. This cutting edge system can reproduce real road resistance based upon the vehicle dynamic model and wheel slip model. This wheel slip function is simulating the real behavior of the powertrain wheel as close as possible at each wheel independently. Additionally, low inertia of dynamometer motor themselves is another advantage for this purpose. This test bed is capable of testing all kinds of 2WD and 4WD powertrain configuration regardless of transmission type. Also, vehicle configuration can be mounted and tested on this test bed with small addition of supporting system alternatively. For the application, a four wheel drive powertrain was mounted on the test bed and driveline noise and vibration behavior such as transfer rattling noise and tip in/out shock were reproduced on this test bed.

The U.S. Environmental Protection Agency has completed a program to demonstrate the feasibility of using integrated catalyst-muffler exhaust systems for nonroad spark ignition gasoline Class I engines (sub-19 kW, less than 225 cc). Integrated catalyst-muffler systems were developed for 4 different Class I engine families. Passive secondary air-injection systems were used with most of the systems to provide an exhaust feed-gas composition that was slightly rich of stoichiometry when used in conjunction with unmodified “Phase 2” carburetor A/F ratio calibrations. Catalyst sizing, PGM loading, and secondary-air venturi design were selected to limit CO oxidation and the typically resultant high heat rejection at high load operating points while still providing good NOx and HC emission control. Infrared thermal imaging was used to assess heat rejection at the EPA A-cycle operational points and during simulated hot soaks for selected configurations.

The U.S. Environmental Protection Agency has completed a program to demonstrate the feasibility of using low-cost engine management systems and modern, high-efficiency exhaust catalysts for nonroad spark ignition gasoline Class II engines (sub-19 kW, greater than 225 cc). Low-cost electronic engine management and fuel injection systems originally developed for motor-scooter and small motorcycle applications were installed on two 500cc single-cylinder spark-ignition lawn-and-garden engines. Integrated catalyst-muffler systems were developed for both engines and fuel control was calibrated to achieve emission control goals while maintaining or improving fuel consumption, engine durability and performance. NOx+HC emissions were reduced approximately 75% and brake-specific fuel-consumption improved by 6 to 12%. .

The scattering properties (influenced by morphology) and refractive index (dependent on microstructure) of engine-emitted soot influences its effect on climate, as well as how we interpret optical measurements of aerosols. The morphology and microstructure of soot from two different engines were studied. The soot samples were collected from a 1.9L Volkswagen TDI engine for two different fuel types (ULSD and B20) and six speed/load combinations., as well as from a Cummins ISX heavy-duty engine using the Westport pilot-ignited high-pressure direct-injection (HPDI) natural-gas fuelling system for three different speed/load combinations. The transmission electron microscopy (TEM) was employed to investigate the soot morphology, emphasizing the fractal properties. Image processing was used to extract the geometrical properties of the thirty-five randomly chosen aggregates from each sample.

The NOx emission and knock characteristics of a PFI engine operating on ethanol/gasoline mixtures were assessed at 1500 and 2000 rpm with λ =1 under Wide-Open-Throttle condition. There was no significant charge cooling due to fuel evaporation. The decrease in NOx emission and exhaust temperature could be explained by the change in adiabatic flame temperature of the mixture. The fuel knock resistance improved significantly with the gasohol so that ignition could be timed at a value much closer or at MBT timing. Changing from 0% to 100% ethanol in the fuel, this combustion phasing improvement led to a 20% increase in NIMEP and 8 percentage points in fuel conversion efficiency at 1500 rpm. At 2000 rpm, where knocking was less severe, the improvement was about half (10% increase in NIMEP and 4 percentage points in fuel conversion efficiency).

Measurements of the soot emissions and engine operating parameters from a diesel engine during transient operation were used to investigate the influence of transient operation on the soot emissions, as well as to validate a realtime mean value soot model (MVSM, [1]) for transient operation. To maximize the temporal resolution of the soot emission and engine parameter measurements (in particular EGR), fast instruments were used and their dynamic responses characterized and corrected. During tip-in transients, an increase in the soot emissions was observed due to a short term oxygen deficit compared to steady-state operation. No significant difference was seen between steady-state and transient operation for acceleration transients. When the MVSM was provided with inputs of sufficient temporal resolution, it was capable of reproducing the qualitative and, in part, quantitative soot emission trends.

A number of studies have been carried out examining the impact of biodiesel blend ratio on vehicle performance and emissions, however there is relatively little data available on the interaction between blend ratio and reduced ambient temperatures over the New European Drive Cycle (NEDC). This study examines the effects of increasing the blend ratio of Rapeseed Methyl Ester (RME) on the NEDC fuel consumption and tailpipe emissions of a vehicle equipped with a 2.0 litre common rail diesel engine, tested on a chassis dynamometer at ambient temperatures of 25, 10 & −5°C. This study found that under low temperature ambient conditions increasing blend ratios had a significant detrimental effect on vehicle particulate emissions reversing the benefits observed at higher ambient temperatures. Blend ratio was found to have minimal impact on hydrocarbon emissions regardless of ambient temperature while carbon monoxide and NOx emissions were found to increase by up to 20% and 5.5% respectively.

This study examines the effects of neat soy-based biodiesel (B100) and its 50% v/v blend (B50) with low sulphur automotive diesel on vehicle PAH emissions. The measurements were conducted on a chassis dynamometer with constant volume sampling (CVS) according to the European regulated technique. The vehicle was a Euro 2 compliant diesel passenger car, equipped with a 1.9 litre common-rail turbocharged direct injection engine and an oxidation catalyst. Emissions of PAHs, nitro-PAHs and oxy-PAHs were measured over the urban phase (UDC) and the extra-urban phase (EUDC) of the type approval cycle (NEDC). In addition, for evaluating realistic driving performance the non-legislated Artemis driving cycles (Urban, Road and Motorway) were used. Overall, 12 PAHs, 4 nitro-PAHs, and 6 oxy-PAHs were determined. The results indicated that PAH emissions exhibited a reduction with biodiesel during all driving modes.

Diesel engines operating in the low-temperature combustion (LTC) mode generally tend to produce very low levels of NOx and soot. However, the implementation of LTC is challenged by the higher cycle-to-cycle variation with heavy EGR operation and the narrower operating corridors. The robustness and efficiency of LTC operation in diesel engines can be enhanced with improvements in the promptness and accuracy of combustion control. A set of field programmable gate array (FPGA) modules were coded and interlaced to suffice on-the-fly combustion event modulations. The cylinder pressure traces were analyzed to update the heat release rate concurrently as the combustion process proceeds prior to completing an engine cycle. Engine dynamometer tests demonstrated that such prompt heat release analysis was effective to optimize the LTC and the split combustion events for better fuel efficiency and exhaust emissions.

New environmental regulations require significant reduction of fuel consumption and engine emissions. This implies improvement of the internal combustion (I.C.) process, reduction of friction, development of complex after-treatment systems, and a reduction of oil consumption. New technical challenges are related to fuel dilution problems in diesel and super-ethanol engines; new wear problems are due to fuel dilution and soot loading in the lubricant; clogging and poisoning problems of after-treatment systems are related to oil consumption, etc. Therefore, researchers and engineers need appropriate tools to better understand and solve these new problems. The paper focuses on the combination of modern engine test beds equipped with innovative radionuclide techniques for real-time oil consumption, oil aeration, fuel dilution, and for on-line wear measurement.

Modern engines rely more and more on the engine oil to serve increasingly complex hydraulic functions such as, for example, controlling cylinder deactivation - a means of significantly increasing fuel efficiency. However, the success of hydraulic methods of activating mechanical responses in engines (or other devices) is dependent on the degree of incompressibility of the hydraulic fluid. As a consequence, those engine oil properties that impart susceptibility to foam formation in areas of hydraulic operations of the engine are detrimental to the engine's performance and durability. This paper is an initial study of aeration, air entrainment, and air release under pressure decrease using a simple bench test. The preliminary information reported suggests the potential application of the instrumental approach developed to measure the rate of foam formation from the air entrained in engine oils and the resistance of such foam to collapse.

A test procedure was set up in our laboratories to evaluate the propensity of fuels and lubricating oils towards the soot accumulation in Diesel Particulate Filters. The experimental work was carried out with the use of a passenger car diesel engine, retrofitted with an aftertreatment system composed by an oxidation catalyst and a DPF. The soot propensity was evaluated by means of repeated measurements of differential exhaust backpressure gradient, during a running period at mid load and speed. The specific fuel consumption gradient was also measured to find a correlation between both the variables. After each soot loading period, a burning off period at full load was operated for the purpose of filter regeneration. A two-phase experiment was undertaken to assess repeatability and discrimination capability of the test procedure. During the first experimental phase, repeated tests were conducted on a fuel matrix containing some surrogate fuels.

The research discussed in this paper clarified the effect of biodiesel fuel (BDF) on two effective deterioration indexes of engine oil, the base number (BN) and the oxidation induction time (OIT). The results of rig tests of oil deterioration using an engine oil mixed with BDF showed that BDF, which contains a large number of unsaturated bonds, accelerates engine oil deterioration.

In present days, most of researches concerned with vehicle engines have been performed to reduce vehicle emissions and to improve engine efficiency. For the requirements, LPG (Liquefied Petroleum Gas) engine which has lots of advantages such as low emission level, cheaper fuel cost and enough infrastructures has had lots of interest as an alternative fuel engine. What is more, it has a low emission level of CO2 well-known as the factor of ‘Global Warming’, thus the use of LPG engines has been increased. Especially since MPI(Multi Point Injection) type LPLi(Liquid Phase LPG injection) system was used for the fuel supply system, disadvantages of LPG engine such as low engine performance, decreased charging efficiency and cold starting difficulty have been improved and prejudices against LPG engines have been changed a lot. In light of this, the motion to use LPLi engines instead of diesel engines has been increasing.

From the end of the 90's, the use of biodiesel fuel (FAME) in blends with petroleum diesel fuel is increasing year after year with a minimum share of 10% defined by the European Parliament for 2020. In parallel, vehicle fleets working with B30 (EN590 - RME) have been developed in France under the impulsion of biodiesel fuel producers. The aim of this investigation program was to determine the impacts of biodiesel fuel blends (higher than 20%) on diesel fuel filters regarding filter clogging and water separation efficiency. Experiments show that high efficiency material with MFP 8μm are not presenting accelerated clogging during laboratory filtration tests with oxidized biodiesel fuels and this is confirmed by analysis of used diesel fuel filters from Euro 4 vehicle field tests using EN590 and B30 fuels.